The comparison of the reinforcing ability of cuttlebone (CTBO) particles in natural and synthetic isoprene rubber (NR and IR, respectively) composites were investigated. The CTBO particles could reinforce in both NR and IR composites. However, the improvement of tensile properties in CTBO-filled NR composites was higher than that of IR composites due to the presence of nonrubber components in NR. The non-rubber components promoted the strong interfacial adhesions with filler and rubbery matrix to increase the bound rubber content. These results affected the increase of the stress softening degree, hysteresis loss, residual strain during cyclic deformation and the volume fraction of constrained rubber region (immobilized area of rubber) in CTBO-filled NR composites. The atomic force microscopy evidently revealed good compatibility between the CTBO particles and the NR matrix due to the presence of organic components from CTBO particles and from non-rubber components in NR. Accordingly, the CTBO particles and non-rubber components play important roles in improving the properties of green rubber composite materials.biocompatibility, mechanical properties, rubber
| INTRODUCTIONNowadays, rubber is one of the widespread and useful materials for industrial applications due to its excellent mechanical properties and high elasticity. 1-3 However, the use of rubber for some purposes requires specific properties to be improved, such as the stiffness, abrasion resistance, dynamic mechanical, or thermal properties, by adding reinforcing fillers, such as carbon black, 2,4-9 silica 10-13 or reinforcing calcium carbonate (CaCO 3 ). 14,15